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arXiv · 2610.06085

Stellarators Linking Axisymmetric Mirrors Part 1: Coil Design, MHD Equilibrium, and Physics Metrics

Rahul Gaur·Djin Patch·Robert Babin·Florian Hindenlang·Xu Chu·Tony Qian
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Abstract

We present a computational design study of a stellarator-mirror hybrid concept, Stellarators Linking Axisymmetric Mirrors (SLAMs), in which an optimized poloidally omnigenous (OP or QI) stellarator serves as the rotational-transform-generating element that links long, axisymmetric (circular cross-section) magnetic mirrors. Starting from an OP precursor configuration obtained from the DESC omnigenity database, we construct hybrid coil sets for field period nFP = 2 SLAMs by separating the OP modular coils along the device midplane and inserting axisymmetric planar mirror coils into the resulting gap. Field-line tracing shows that nested vacuum flux surfaces survive this extrusion across a range of mirror-section lengths, with the cross-section qualitatively preserved at the point where the mirror is inserted. We use the field-line tracing data to map the shape of a surface and use the GVEC fixed-boundary solver to calculate an ideal magnetohydrodynamic (MHD) equilibrium and evaluate physics metrics such as the neoclassical transport proxy (eps_eff), the vacuum magnetic well (W), and the gyrokinetic heat fluxes (Q), providing a first-principles analysis of such concepts using modern stellarator analysis tools.

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Rahul Gaur, Djin Patch, Robert Babin, Florian Hindenlang, Xu Chu, Tony Qian. 2026-10-05. Stellarators Linking Axisymmetric Mirrors Part 1: Coil Design, MHD Equilibrium, and Physics Metrics. https://arxiv.org/abs/2610.06085

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